This is for signing up for their Amazon Prime Rewards Card, There are no fees of any kind as long as you pay the card on time, and the $100 is added to your amazon account immediately upon approval, it takes ~5 mins to sign up, one of the easiest credit card signups ever. you don't even need to use the card if you don't want to, just get the gift card from signing up for it and then never put any charges on it, there's no annual fee or any sort of fee for not using it, however, it is a decent credit card in terms of rewards, benefits, and cashback so you may decide it is worth using, had mine for around a year, no issues, great way to allow your self to justify spending money on that thing you've wanted to by for a while, for me it was a fancy pair of headphones. Thanks for using my referral.